Abstract: A carbonylation catalytic system comprises (A) a combination of (A1) a Group VIII metal source of Periodic Table of the Elements (e.g., palladium, palladium chloride) supported on a carrier, (A2) a ligand such as triphenylphosphine and (A3) an acid such as an alkyl-sulfonic acid, or (B) a combination of (B1) the Group VIII metal source except for palladium (e.g., a platinum compound), (B2) a ligand such as triphenylphosphine and (B3) an electron donative compound having an electron donability .DELTA..nu.D of not less than 2 (for instance, an amine such as a heterocyclic tertiary amine). The catalytic system (B) may further comprise (B4) an acid such as methanesulfonic acid.

Abstract: Methyl 2-hydroxy-4-methylthiobutanoate and formamide are produced by means of reacting 2-hydroxy-4-methylthiobutanamide obtained by hydration of 2-hydroxy-4-methylthiobutyronitrile with methyl formate. Said methyl 2-hydroxy-4-methylthiobutanoate is hydrolyzed to give 2-hydroxy-4-methylthiobutanoic acid and methanol. No sulfuric acid is employed as a reacting agent, hence exhaustion of a large quantity of ammonium sulfate is prevented. Formamide and methanol thus produced can be recycled as reactants.

Abstract: Plural types of register mark configurations are displayed in window W1, and a specified page layout pattern is displayed in window W2. A plurality of register mark candidate positions, which can be decided according to the page layout pattern, are also displayed in window W2. The operator selects one of the register mark configurations available and also selects a register mark candidate position to locate the register mark. The selected register mark will be located at the selected candidate position after rotation by the specified rotation angle.

Abstract: A catalyst for preparing .alpha.,.beta.-unsaturated aldehydes by the gas phase catalytic oxidation of .alpha.,.beta.-unsaturated hydrocarbons, which catalyst contains as indispensable metal components molybdenum, bismuth and at least one transition metal selected from iron, nickel and cobalt. A chelating agent, or a chelate compound of any of the metals comprising the catalyst, is added to all or some of the starting liquid mixtures during the catalyst preparation stage, whereby to increase the catalytic activity of the catalyst so that the desired .alpha.,.beta.-unsaturated aldehyde products such as acrolein and methacrolein can be obtained in high yields. In catalysts of this type, the catalytic activity can be maintained at a high level even if the catalyst does not contain an arsenic component.

Abstract: A catalyst for preparing .alpha.,.beta.-unsaturated aldehydes by the gas phase catalytic oxidation of .alpha.,.beta.-unsaturated hydrocarbons, comprising as critical metal components molybdenum, bismuth and at least one transition metal selected from iron, nickel and cobalt, said catalyst being prepared by adding ammonium rhodanide to all or some of the starting liquid mixtures containing said catalytic metal components.